View clinical trials related to Chromosome Aberrations.
Filter by:The purpose of this study is to assess the hematological and cytogenetic responses with 5 azacytidine in patients over 55 years of age with MDS/AML due to chromosome 7 abnormalities and to assess the hematological and cytogenetic response rates in patients with relapsed AML and chromosome 7 abnormality.
The overall significance of this study is to develop a laboratory developed test (LDT) to use a new marker in the maternal blood to better identify pregnancies that have a child with a chromosome abnormality such as Down syndrome (trisomy 21), Edward's syndrome (trisomy 18), Patau syndrome (trisomy 13), Klinefelter syndrome, (47, XXY), and other chromosome abnormalities. Accomplishing that task would reduce the need for invasive amniocentesis and CVS procedures.
An increased incidence of aneuploid pregnancies has been reported in women of advanced maternal age, with higher miscarriage rates. Cytogenetic studies in preimplantation embryos have shown elevated aneuploidy rate, particularly in women over 38 years. For these reasons, PGS has been applied to these patients to improve ongoing implantation rates, and most importantly, to decrease the risk of further miscarriages and affected offspring. In the past two years, several RCT have raised the question whether PGS is benefitial or not in AMA patients. In our experience, PGS outcome in these patients offers higher ongoing implantation rates than the previously published in RCT studies, where no benefits for PGS were found. In these papers, poor technical skills, as well as unclear patients selection could explain the reported lack of PGS benefits. Therefore, the objective of the present RCT is to analyze the outcome of IVF cycles with and without PGS in two age groups: - Patients 38-39 years of age: 200 cyles per arm reaching embryo transfer should be performed - Patients 40-44 years of age: 120 cycles per arm reaching embryo transfer Sample size has been calculated according to our retrospective experience with higher differences in ongoing implantation rates between cycles with and without PGS in patients of 40-44 years of age. In all patients embryo transfer will be performed on day 5. In the PGS group one cell will be biopsy in embryos with ≥5 cells on day-3 and chromosomes 13, 15, 17, 18, 21, 22, X and Y will be analyzed in two rounds. In the third round, nuclei with undoubtful or non-conclusive results will be analyzed using subtelomeric probes.
The goal of this pilot project is to determine whether melatonin levels are disordered in patients with Smith-Magenis Syndrome (SMS) and whether melatonin treatment can correct abnormal circadian rhythms in SMS patients. In addition, the study investigates the effects of bright light in an elderly control population that exhibits low melatonin secretion.
Optimise genetic screening of human embryos using higher resolution techniques
Premature ovarian failure (POF) is known to be associated with an increased risk of ocular surface disease (dry eye), likely due to the reduction of both estrogens and androgens seen in this condition. From preliminary data, we suspect that women with Turners syndrome (45, XO), a genetic abnormality that affects sex hormone levels, are also at increased risk of ocular surface disease. Comparing POF and TS women may allow us to distinguish different mechanisms for ocular surface disease, due to the different etiologies of hormonal (estrogen and androgen) alterations posed by POF and TS.
In order to distinguish between clonal instability driven by imatinib in CML and actual changes with secondary clones induced by imatinib we would like to investigate the karyotype of non-CML patients treated with imatinib such as GIST patients.
This study will assess the frequency of chromosomal abnormalities measured in circulating lymphocytes in treatment-naive children with Attention Deficit Hyperactivity Disorder (ADHD) treated for 3 months with either extended release methylphenidate or behavioral therapy.
Ionizing radiation efficiently induces chromosomal aberrations (CA) and several studies of CA have now been conducted among small groups of flight crews. However, most of the studies only evaluated the unstable aberrations that reflect recent exposures, but not long-term cumulative cosmic radiation exposure. Chromosome painting by fluorescence in situ hybridization (FISH) is a widely used and established cytogenetic method for detecting stable aberrations such as translocations. Thus, FISH can be used for estimating chromosomal damage from cumulative radiation exposure. No large studies of flight crews utilizing FISH have been conducted to date. We propose a study to measure CA using FISH in a group of pilots estimated to have high comic radiation exposure based on flight histories, i.e., those with long duration flying international routes, and a comparison group of university faculty with minimal flying history. These measurements will be used to determine if pilots have elevated frequencies of CA (specifically stable translocations) as compared with the university faculty. In addition, the frequencies of CA will be examined in relation to the cumulative cosmic radiation dose to determine if there is a dose-response relationship. Individual cumulative doses will be calculated from pilot flight histories using a computer program developed by the FAA which estimates cosmic radiation does by accounting for changes in altitude and latitude, and the 11-year solar cycle at the time of the flight. We will collect information on age, lifestyle factors, diet, health history, family cancer history, and medical radiation exposures from personal interview and self-administered dietary questionaire. These factors may affect the CA frequency and so we plan to adjust for them in the statistical analyses. Pilots will be identified based on the Allied Pilots Association roster and faculty from a commercial company that maintains a database of university faculty, including those in the Chicago area. Potential participants will be notified of the study by mail and recruited/screened for eligibility over the telephone. We will compensate participants $100 for their time. A field station will be set up at a medical or health clinic convenient to the participants, where interviews Will be conducted and a peripheral blood sample collected. Participants will be notified of the overall study results and may request their personal CA results at the end of the study. Participants may also choose to have additional blood drawn, however this blood sample will be anonymized so that it cannot be linked back to the participant. Genotypic variants in DNA repair (and possibly other) genes will be evaluated for an effect on CA frequency.
Our vision, that of the researchers at the University of Texas Health Science Center at San Antonio, is that every person with a chromosome 18 abnormality will have an autonomous and healthy life. Our mission is to provide families affected by chromosome 18 abnormalities with comprehensive medical and educational information. Our goals are to provide definitive medical and education resources for the families of individuals with chromosome 18 abnormalities; perform and facilitate groundbreaking clinical and basic research relating to the syndromes of chromosome 18; and to provide treatments to help these individuals overcome the effects of their chromosome abnormality.